1. Field of the Invention
The present invention is related generally to windscreen wiper devices for automobiles and more particularly to hybrid windscreen wiper devices.
2. Related Art
The majority of automotive windscreen wiper devices, or wiper blades, can be categorized as either conventional-style wiper blades (hereinafter referred to as “conventional blades”) or beam-style wiper blades (hereinafter referred to as “beam blades”). Conventional blades typically include an elongated wiper strip; at least one carrier element (also known as a flexor); and a frame structure with a connecting device for attachment to a wiper arm, plurality of linkages and a plurality of claws. The carrier elements are generally linearly shaped when in a relaxed state, and the frame structure distributes a force from the wiper arm across the lengths of the carrier elements and the wiper strip while allowing the carrier elements and wiper strip to flex and conform to the curvature of a vehicle's windshield. This establishes a seal between the wiper strip and the windshield. Typically, either claws in the frame structure in is clamped into engagement with the carrier element or elements or the carrier elements are deformed on either side of one set of claws to prevent the wiper strip and carrier element or elements from detaching from the frame structure. Either of these configurations may be costly and also may restrict movement of carrier elements and the wiper strip relative to the frame structure.
Beam blades, in contrast to conventional blades, lack a frame structure. Instead, the carrier elements of beam blades are curved when in a relaxed state and the connecting device is attached directly to the carrier element or elements. When a beam blade is pressed against a windshield, the curved carrier elements conform the wiper strip to the curvature of the windshield and press substantially the entire length of the wiper strip against the windshield to establish the seal between the wiper strip and the windshield. Beam blades also typically include one or more spoiler elements, which use a flow of air over the beam blade to apply a down force on the carrier elements and the wiper strip while the vehicle is in motion to further press the wiper. Generally, at least a pair of end caps and the connecting device are clamped, latched, welded or staked into engagement with the carrier elements, which restricts movement of the carrier elements relative to these components. Typically, the end caps are deformed to include notches or other features which facilitate their connection with the end caps.
Some wiper blade manufacturers have begun producing and marketing “hybrid blades” which include certain features from both conventional and beam blades. Such hybrid blades typically include the frame structure similar to conventional blades, but the frame structure is covered by a spoiler-shaped cover piece that is disposed over the frame structure. This gives the otherwise conventional blade the down force effect of beam blades. Typical hybrid blades include a plurality of claws in engagement with one or more carrier elements with at least one set of those claws being clamped or otherwise latched into engagement with the carrier elements.